Des Moines (DSM) to St. Louis (STL): On-Time Performance
Data through May 2026
The calendar drives reliability on DSM–STL. September 2024 flights landed on schedule 98% of the time, but July 2024 dropped to 76% — a gap of 22 points. Across the full period the route averages 89% on-time against a national 78%. Morning departures also hold up better than evening ones (94% vs 77%), which matters most in the rough months.
- On-time
- 89%
- arrived <15 min late
- Avg delay
- 7 min
- completed flights
- Cancelled
- 0.6%
- Flights/day
- 1.4
- last 12 months
- Duration
- 1h 9m
- scheduled
- Distance
- 259 mi
Monthly on-time trend
Best time to fly from DSM to STL
Aim for departures around 3 p.m. (97% on-time); avoid 6 p.m. departures (74%).
By day of week
| Day | On-time | Avg delay |
|---|---|---|
| Monday | 86% | 7 min |
| Tuesdaybest | 97% | 2 min |
| Wednesday | 89% | 5 min |
| Thursday | 86% | 12 min |
| Friday | 92% | 5 min |
| Saturday | 84% | 17 min |
| Sunday | 85% | 8 min |
What causes delays on this route
Share of total delay minutes by cause, as reported by carriers to the US DOT.
- Late-arriving aircraft38%
- Airline operations34%
- National airspace system19%
- Weather9%
Frequently asked questions
- How often are flights from DSM to STL delayed?
- 11% of DSM–STL flights arrived 15 or more minutes late (the US DOT definition of a delay) between 2024-06 and 2026-05. The average arrival delay across completed flights was 7 minutes.
- What is the best time of day to fly from DSM to STL?
- Departures around 3 p.m. have the best record (97% on-time), while departures around 6 p.m. have the worst (74%). As on most US routes, delays accumulate through the day, so earlier flights are generally safer.
- How long is the flight from DSM to STL?
- The scheduled DSM–STL flight time averages 1h 9m over 259 miles. Actual arrival times vary — flights on this route land 15+ minutes late 11% of the time.
- How often are DSM to STL flights cancelled?
- 0.6% of scheduled flights on this route were cancelled between 2024-06 and 2026-05, at or below the national rate of 1.6%.
- What is the worst month to fly from DSM to STL?
- July 2024 was the roughest month in this dataset, with only 76% of arrivals on time. The best was September 2024 at 98%. If your dates are flexible, that 22-point gap is worth planning around.
Explore related pages
More routes from DSM
Based on 1,194 flights, 2024-06–2026-05. Source: US DOT Bureau of Transportation Statistics. Updated 2026-07-01.